Alright check it out, I m get some pre-ignition when the engine is under a heavy load. I just rehooked up my knock sensor, and it help alittle bit but still got some under a heavy load. Well I just changed out the knock sensor and cleaned out the crud that built up, It was basically blocking up the coolet. Well its still doing it, I run only premium so its not the gas. So I m pretty much at a lost right now. What else could it be? Oh basic time is at 8 degrees right now, I m going to bump it back down to 6 tomorrow. Any ideas?

 

what motor do you have, is it stock?

 

oh its a 89 L98

 

well the heads and cam is stock, But i got all the bolt ons, headers, 3inch catback, high flow bass, slp runners, msd ignition, ported pleum, and smog stuff and egr delete.

 

Do you have a vacuum leak? Carbon build up? I tried figuring out for monthes why my 91 RS was pinging. I replaced the IAC, ignition module, plugs twice before I got around to pouring some water down the intake to clean the carbon out.

 

Well the intake is new, and so are the plugs and wires, module and I scrabbed the crap out of the IAC. Yeah so their shouldn't be any carbon, I m thinking about just yanking out the knock sensor again to make sure all the stuff will get out of there again. Man its driving me crazy, I want to run it at the track, the Iroc is running like a beast now, But I don't want to take the chance of blowing a head gasket. Does anyone have any ideas?

 

well I think I m running alittle rich if that helps

 

try running colder plugs

 

what do you mean colder plugs?

 

by colder i mean colder heat range. i believe the standard plug for camaro 350s is a delco r45ts. the 45 is the heat range, an r43ts is two ranges colder. the cause of preignition or ping is the air/fuel mixture igniting before the spark occurs. this happens because the high temperature in the cylinder is not being dissappated quickly enough. by varying the amount of ceramic in a spark plug exposed to the combustion chamber, the plug will suck heat out at different rates. more ceramic=colder temp. because there is more material available to transfer heat. if you run too hot a plug you'll get detonation or preignition, too cold a plug and it'll foul out quickly so i'd start with plugs one heat range colder than what you have now, if it still pings drop one more.

first off i'd set the right timing. right now it's igniting 2° earlier than it should and since you dont have any internal mods you shouldn't need to adjust timing. so maybe what you think is ping is actually just your timing too advanced.

 

well it isn't the timing I know that cause I had it set to 6 degree a couple of days ago, but check it out I think I found out whats wrong. I just scanned my car and got code 42, I think I got a bad knock sensor. I know it isn't the wire cause I had the code before and replaced and hooked up the wire and the code went away. Now that I put this new one, in the code is on again. So I m going to take it back, I m going to try to put the old one back end because it was working but there was a wall of crud behind it. So I think that might do it. And I m going to set the timing back down to be sure too. I ll let you know how it works out.

 

oh my bad I just looked in the book and seen that 42 is the ignition module, well I just changed it out like 6 months ago, I m going to check the connection, thats one of the connectors that broke, well the clip anyway so i m going to mess with tommorrow after there is light

 

we get signal

all your base are belong to us

 

dacuma,

i tried to respond to your email but my server rejected your address for some reason

original message:
alright well I m fighting still fighting this pre-ignition prob, I got a
new
> idea though, now you were telling about the a colder plug. Well I didn't
get
> any prob like this till I put the new motor in, the only thing different
is
> that I got my headers in, and I put in the Accel shorty plugs. Now could
the
> shorter plugs becausing the pre-ignition?


here's my reply:
the shorter plugs shouldn't make a difference as long as they're the correct
heat range, based on your mods i think the stock heat range should be the
one you need. in the past few days the subject of spraying water in your
intake has come up again, you might try this also. get a spray bottle and
mist about 8oz of water in your throttle body while revving the engine, when
the water vaporizes it's expands greatly and is supposed to break up the
carbon build up in your cylinders. i thought this was BS at first but i
searched on it and a lot of people say it's helped, including Vader. make
sure you engine is fully warmed first. carbon can cause you to ping because
it builds up heat spots that don't dissipate. good luck.